The increasing integration of LSIs has led to finer and finer circuit line widths of semiconductor devices. An approach employed to form desired circuit patterns on semiconductor devices uses a step-and-repeat exposure system to reduce and transfer, onto a wafer, a high-precision master pattern (also called a mask, or a reticle particularly when used in a stepper or scanner) formed on a piece of quartz. The high-precision original pattern is written with an electron beam writing apparatus by use of a so-called electron beam lithography technique.
Processes such as fracturing and format conversion suitable for an electron beam writing apparatus are applied to design data (CAD data) outside the writing apparatus (in an external apparatus), thus creating write data based on the format used for the writing apparatus. The write data is transferred/input to the writing apparatus, and undergoes a data registration process including multiple stages of processing, such as format check and calculation of shot density.
Design data and write data each have a plurality of pieces of chip data including information such as chip structure, and layout data including information such as where individual chips are placed. The chip data is divided into a plurality of frames, and processes such as data conversion in an external apparatus and data registration in the writing apparatus are executed in a pipeline processing to improve processing speed.
In related art, write data is registered (input) into the writing apparatus on a per-layout basis. Data registration in the writing apparatus is started after all of chip data and layout data have been processed in the external apparatus. This makes it difficult to reduce the turn-around time (TAT) of the writing process.